The "rave" phenomenon has been a major element in the resurgence of psychedelic drug use in Western society. Raves are characterized by large numbers of youth dancing for long periods of time and by the use of "club drugs," such as 3,4-meththylenedioxymethamphetamine (MDMA or "ecstacy"). While a small body of research has explored the use of ecstasy and other club drugs (EOCD) among club rave attendees in the United States, 2 major limitations remain. First, no studies have investigated the relationship between EOCD use and high-risk sexual behavior, a known risk factor for HIV transmission, among members of this population. Second, the extent to which club owners and rave promoters would be receptive to a community-level, EOCD- and high-risk sexual behavior-related preventive intervention is unknown. To address these critical gaps in the prevention arena, this B/START application involves a mixed-method design that, first, explores the association between EOCD use and high-risk sexual behaviors among club rave attendees along the Baltimore-Washington, corridor, and second, assesses the feasibility of a community-based preventive intervention within these settings. First, self-reported drug use data and information on high-risk sexual behaviors will be collected from rave attendees. Second, club owners and rave promoters will be queried about their receptiveness to a community-level EOCD-related preventive intervention. The 2 aims of this study are: (1) to elucidate those characteristics of rave attendees that signal increased EOCD involvement and co-occurring high-risk sexual behaviors; and (2) to identify venues for future preventive interventions and to assess the extent to which club owners and rave promoters would be receptive to a community-level, EOCD-related prevention intervention.